sturtevant



July 24, 1928. 1,678,450 H. E. STURTEVANT CHAIN AND PART THEREFOR FiledOct. 25, 1923 4 Sheqts-Sheet 1 A TTORNEYS.

July 24, 1928. 1,678,450

- H. E. STURTEVANT CHAIN AND PART THEREFOR Filed Oct. 25, 1923 4Shoots-Sheet 2 glo ATTORNEY);

July 24, 1928. 1,678,450

H. E. STURTEVANT CHAIN AND PART THEREFOR Filed Oct. 25, 1923 4Sheets-Sheet 5 I I uli." L- l gawfw R BY r. -ATTORNEY5.

July 24, 1928.. 1,678,450

H. E. STURTEVANT CHAIN AND PART THEREFOR Filed 001:. 25, 1923 4Sheets-Sheet 4 24; ATTORNEYS. I

Patented July 24, 1928.

UNITED STATES earner OFFICE.

HAROLD E. STURTEVANT, 01F HARTFORQ, CONNECTICUT, ASSIGNOR TO THE WHITNEYMFG. (30., OF HARTFORD, CONNECTICUT, A CORPS.

.....T;Ll: 1"l C-F CONNECTICUT.

CHAIN AND rarer rnnnnron.

Application filed October 25, 1923.

My invention relates to link chains of the silent type and consists outo "tain novel parts and combinations of parts to render the chaincilicient, di'irable and noiseless in operation which novel parts andcombinations will be specifically descriliied herein and pointed out inthe appended claims.

My invention will. he better understood hy reading the followingdescriptioiii taken in connection with the drawings showing oneembodiment thereof and in which Fig. 1

a side view of a portion oil? a chain containing one einhodin'ient of myinvention; Fig. 2 is an inverted sectional. view taken on the plane ofthe line Il-ll oi Fig. 1; Fig. 3 is a side view ot a single link; Fisectional elevation. on a scale larger than the preceding figuresillustrating the positions assumed by the links of adjacent pitches andthe pin passing through the openings therein on a straight run of thechain; Fig. 5 is a view similar to Fig. 4', illustrating the jointbetween the two pitches in the tiered position; Fig. 6 is a sectionalelevation of: a modification. with the links of adjacent pitches in thepositions assumed on a straight run of the chain; F 7 is a view:eiinilar to Fig. 6 with the links of adjacent pitches ties. ll; Fig. 8is a sectional eleva lion ol' :1. turther modification showing thepositions assumed by the links of dCelilCSiil) pitches and the pin on astraight run of the chain; Fin. 9 is a view similar to Fig. 8 showing.the positions 011 the links of adjacent pitches and that of the pin inthe tlexed position; Fig. 10 is a sectional. elevation of a furthermodification showing the positions assiuned by the links of adjacentpitches and the pin on a straight run of the chain; Fig. 1.1 is viewsimilar to Fig. 10, showing the links in the flexed posi ion; Fig. 12 isa sectional ele ation of a further modification illustrating thepositions assumed by the links oi. adjacent pitches and the pin on astraight rm: of the chain and Fig". 13 is a view similar to Fig. 1.2with the links of adjacent pitches flexed.

Referring to the embodiment shown in Fig 1 to 5. the chain comprises aplurality of links 1 arranged side by side and a plurality of similarlinks 2 arranged side by side and overlapping the ends of the links 1.Each oi the links 1 and 2 is provided at each. end with a similaropening. From an inspection of Figs. 1 and 3 it will be noted Serial No.670.636.

that the openings 3 in the ends of the links are at a slight angle tothe vertical. This angle is approximately 8, but may be made greater orless, it desired. The openings flare. outwardly from the pivotal centersl, the sides 5 and 12, being curved. The side 5 is a segment of a circlewith its center on a line ('3 passing through the pivotal centers 4-and, extending}; below and at an angle of about 8 to said center line Mand the side 12 is a segment of a circle whose center is on the line 6passing through the pivotal centers 4!: and which line extends above andat an angle of about 8 to said center line 1.4. Thueliare, the centerline Cl the openis at an angle of about 8 to a vertical line par 1. 3;through. the pivotal centers.

The ends 7 and 8 of the openings are con-- centric with the pivotalcenters 4.

Pins 9 are placed through the registering openin s in the ends of theoverlapping links 1 2. These pins curved from edge to edge and haveparallel surfaces. One of these surfaces. 13, is concave and the otheris convex. In the straight run of the chain the links 1 and 2 and pins 9assume the posi tions shown in t. From Fig. i, it will he noted that thecenter line of the opening 3 in the link i. and the center line of theopening in the link 2 are at an angle of about 16 to each other. Thesides 5 ol the links 1. the convex side of the pins at points nearer thepivotal. centers of the links than the points of engagement of the sides5 of the openings in the links 2 on the concave side of the pins. Thiscauses the upper portion of the pins to engage the s. 12 of the links 1at points As the joint is flexed from the position shown in Fig". l: tothat 5. the surfaces '5 of the links 2 move up and engage the pins 9points further away from the pivotal center of the pin than the pointsof engagement between the sides 5 ot the links 1 and the pins. Thiscauses the pins to touch the sides 12 of the links 1 at points Y. Thefact that the points of one; ement between the links of adjacent pitch sand the pins are not in a line parallel to the center line of the chainbut in a line at an angle thereto, creates a resultant of force whichtends to take the curvature out of the pins. This arrangement,therefore, adds a slight resiliency to the joint and has a tendency toreduce the noise of the chain, but not sulticient to permit the chain to'bstantially increase in length under load.

tiulicient clearance exists between the l and 11 of the pins 9 and thelinks so as to relieve any excess :triction that might otherwise developat these points. The ends 7 and 8 of the openings are concentric withthe pivotal centers 4 and the pins 9 stand in the position shown in igs.l to at in the straight run of the chain and shown in when the chain istiered. That is to say; the pins are ly tilted as above explained.

As the links oi adjacent pitches move relative to each other from thepositions shown in i. to those shown in Fig. 5, the sides h of the links1 and 2 rockupwardly on th: sides of the pins from the positions sheenin 4 to those shown in 5. This rocking movement of the links. on theliat tacos ol' the pins is accomplished wi h a llllt'llllllll'll fricton and noise with the resu tant u'iinin'mn'i of wear and maximumelticiency.

The opposite sides 12 ot the openings of the links 01" adjacent pitchesdo not engage the pins when the chain is under tension and, tl'ierctoredo not take any active part in the operation of the chain.

The pins 9 are generally rectangular in cross section with the edges and11 rounded. These pins are preferably made by rolling rods to the crosssection shown. li the use or pins ot simple cross section, the same maybe manutactured inexpensively and the cost oi the chain thereby reduced.The pins shown in this appli ration may be made trom what is termedstock material.

In the arrangement shown in 6 and T. the pins are each divided into twoparts and The corresponding parts of this structure are numbered thesame as in Figs. 4 and 5 but have the exponent a applied tiercto. In theconstruction shown in Figs. 6 and 7, the thickness of the pin s a wholein the center line of the chain "rcater than in the form shown in Figs.and 5. Since the two contacting flat faces of the two members A and B ofthe pin are not perfect planes but are necessarily slightly irregular.there will be a small amount or elasticity in the joint of the termshown in Figs. 6 and 7. The resiliency orelasticity has the eli' ect 0treducing the noise of the chain. If desired, the two members A and B maybe madeinto a single piece.

In the modification shown in Figs. 8 and 9, the pins are composed of twomembers A and B, the member A being curved and the member B beingstraight. Otherwise, this modification is similar to that shown in igs.(3 and 7 and corresponding parts are similarly indicated but have theexpoand is made of a single piece oi nent b applied thereto. By thearrangement. shown in Figs. 8 and f), the member A has a rolling contacton the member B so that when the joint is flexed the parts move from thepositions shown in Fig. 8 to the positions shown in Fig. 9; that is tosay, the sides 5" of the links 1 roll upwardly on the members l3 and thememhers A roll. upwardly on the members B at the same time the sides 5roll upwardly on the concave sides of the members A. There are,therefore, three sets of rolling contacts in this modification whichhave the etl'ect oi? reducing the friction of the joint and therebyrendering the chain more efiicient. The tact that the member A isslightly cu ved also adds resiliency to the joint which has the etiectof reducing the noise. i

In Figs. 10 and ll is shown a modil'icw tion similar to that shown inFigs. 8 and 9 except that both the members A and B are curved. Themembers A have a slightly greater curvature than the members B. Thesemembers are so placed that the conyer: sides ott the members A engagethe concave sides of the members ii. The sides 5 of the links 1 engagethe convex suri'aces ot' the members B and the sides D oi? the links 2engage the concave sides of the members This modification like thatshown in Figs. 8 and 9 has three sets of rolling contacts and thecurvature of the members A. and B adds slightly to the resiliency of thejoint.

In Figs. 12 and 13. 1 have shown a Form oi joint which in many respects,is pref-- erable to any of the joints shown in this application. In thisterm oi? the invention. the pin 9 is straight trom edge to edge l andis, therefore. very simple in structure and to ifr.

easy to manufacture. The pin may be mat by rolling the sane trom a metalrod suitable cross section. The action of tie hat links on this pin isidentical with form shown in Figs. 6 and 7. The chief ditl erencebetween these two modin' eions that the pins in Figs. 12 and are made ofa single piece. whereas in .318. G and 7 two similar pieces are used.

The side walls of the opening in this modification are the same as thoseshown. and hereinafter described. In this form I have shown links 6 and15 intersecting at the pivotal centers 4:. The side walls of the openingin the link 1 have their centers on the link 6 and the side walls of theopening in link 2 have their centers on the link 15. The links 6 and 15are at an angle of about 16 to each other. Each. 01 these links is at anangle of approximately 8 to the center line 14- of the link.

I wish to call attention to the fact that in ill! all of themodifications shown and described the opposing contacting surfaces 5 ofthe links on the pins travel upward on the pins as the joints areflexed. In each instance shown these points are below the center line ofthe chain during the straight run of the chain as shown in F 4, 6, 8, 10and 12, whereas, they are above the center line of the chain when thejoints are flexed as shown in Figs. 5, 7, 9, l1 and. 13.

Chains which I have constructed like each of? the n'i'odilications shownhave upon test shown that they do not chew up" the sprocket wheels as docertain other chains constructed along other lines and from which thefeature above described is absent. It is, therefore, my present beliefthat the chewing up action is avoided by so arranging the joints thatthe opposing contact surfaces of links of adjacent pitches may move frombelow the center line of the chain to above the said center line as thejoints are flexed around the V "ockets.

From the foregoing, it will be seen that in all the forms shown pins areused which. may be easily and inexpensively manutactured from stockmaterial. One or more members made from such material may be used as apin, depending upon the circun'istances under which the particular chainis to be used. Rolling contacts are provided in. each case therebyreducing the friction to a minimum and increasing the eliiciency andlife of the chain. In some instances. the resiliency has been impartedto the joint by bending or otherwise arranging one or both oi" themembers constituting the pin therel y lessening the noise usuallypresent in chains of this type. The openings of the links are so formedthat the links are intercln'uigeable, thereby greatly lessening then'ianuttacturingcost and facilitating the automatic assembly ot thelinks in the chains.

lt will be noted from Figs. 1 and 2 that the ends oi. the pins 9 areriveted over adacent the outside links 1 and that no waslr ers areplaced between the ends of the pins and the links. This simplifies thestructure of the chain and also lessens the cost of manufacture without,in any manner, decreasing the efficiency of the chain.

Slight changes may be made in details without departing from the spiritof my invention.

I claim:

1. A chain of the silent link type having joints comprising links withregistering openings and two pin members in said openings, said membershaving parallel sides and the side walls of said openings being curvedand havii'ig rocking contact with said pin members.

2. A chain of the silent link type having joints comprising links havingregistering openings flaring from the pivotal centers the side walls ofsaid openings being curved, two pin members in said openings, saidmembers having adjacent parallel ...des and so arranged that the s ccwalls of said 0penings ffOIITl rockingcontact with the other sides ofsaid members.

A chain oi? the silent link type having joints cmnprising links havingregistering openings flaring from the pivotal centers the side walls ofsaid openings being curved, two pin members in said openings eachhaving); a. substantially rectangular cross section and arram .d side byside, the side walls of said openings engaging said pin members to formrocking joints therewith.

4. 11 chain of the silent link type having joints con'iprising linkshaving registering openings flaring from the pivotal centers the sidewalls of said openings being curved plurality of pin members placed sideby side andv having parallel contacting surfaces, the side walls of thelink openings en gaging the outside surfaces o'l said members and 'lorining rocking contacttherewith.

5. A chain oi. the silent link type having joints comprising linkshaving registering openings flaring from the pivotal centers the sidewalls of said openings being curved, a plurality of similar pini'nenibers placed, cdgewise in said openings and the side walls of saidopenings forming rocking contacts with said members. i

6. A. pin for silent link chains comprising a. plurality of memberssubstantially rectangular in cross section.

HAROLD E. STURTEVANT.

